This invention relates to a motorcycle and more particularly to a frame and body construction therefore that permits the rider to assume a wide variety of attitudes on the motorcycle and be comfortable in all such positions.
As is well know, motorcycles are constructed primarily for the type of road and riding conditions which they are expects to encounter. One type of motorcycle is designed primarily for riding in off-the-road or rough terrain conditions or in competition such as Moto crossing. This type of motorcycle must have a very robust frame and also must provide a seat arrangement that permits the rider to assume a wide variety of riding postures depending upon the riding conditions.
Generally the frame for such types of motorcycles includes a head pipe and a tubular main frame that extends rearwardly therefrom and which mounts the fuel tank. Frequently, this type of motorcycle is provided with a full or partially water cooled engine and the radiator is positioned at the front of the frame. A pair of radiator covers are disposed on the opposite sides of the radiator so as to direct the air flow across the core of the radiator.
Generally it is the practice to provide a relatively long seat that accommodates various riding positions for the rider. In addition, the rider likes to have the frame and body in such a manner that the rider may place his legs in close contact with it, much akin to a rider on a horse for stability. Under other conditions, the rider likes to place one or both of his feet forwardly for bracing purposes. The type of motorcycle described and frame construction therefore permits such riding postures by the rider.
However, due to the extremely rough use that such motorcycles encounter, it is desireable to provide a stronger and more robust frame. Therefore, it has been proposed to provide a frame assembly having a head pipe and a pair of main frame members which are formed as rectangular box sections and which extend rearwardly from the head tube backwardly toward the rear wheel. These main frame members generally diverge from a longitudinal center plane of the motorcycle in an angular fashion and thus provide a somewhat irregular configuration in the area of the legs of the rider. This problem is compounded when a radiator and radiator covers are provided for directing the flow of air across the radiator. With motorcycles of this type previously proposed, the rider has been somewhat limited in ability to move freely from one riding position to another.
It is, therefore, a principal object of this invention to provide an improved motorcycle arrangement having a robust frame that lends itself to off-the-road use and wherein the sides of the motorcycle are relatively smoothly configured so that the rider can conveniently move riding positions.
It is a further object to this invention to provide an improved and relatively smooth frame and body construction for a motorcycle that permits a rider to move to various riding positions freely and without incumbrance.
In connection with the frame assembly of the type described embodying box type main frame members, it has been the practice to have the main frame members extend generally perpendicularly back from the head pipe and then bend downwardly to support the rear wheel suspension system. Of course, such bends in the frame construction can give rise to stress risers which can only be compensated for by employing heavy frame members.
It is, therefore, a still further object to this invention to provide a frame construction having box like main frame members which can extend straight back from the head pipe without having stress inducing bends.